Dark Energy: The Biggest Mystery in the Universe

At the South Pole, astronomers try to unravel a force greater than gravity that will determine the fate of the cosmos

By Richard Panek
Smithsonian magazine, April 2010, Subscribe

Far from light and plunged into months-long darkness, Antarctica's South Pole Telescope is one of the best places on Earth for observing the universe. (Keith Vanderlinde / National Science Foundation)

Twice a day, seven days a week, from February to November for the past four years, two researchers have layered themselves with thermal underwear and outerwear, with fleece, flannel, double gloves, double socks, padded overalls and puffy red parkas, mummifying themselves until they look like twin Michelin Men. Then they step outside, trading the warmth and modern conveniences of a science station (foosball, fitness center, 24-hour cafeteria) for a minus-100-degree Fahrenheit featureless landscape, flatter than Kansas and one of the coldest places on the planet. They trudge in darkness nearly a mile, across a plateau of snow and ice, until they discern, against the backdrop of more stars than any hands-in-pocket backyard observer has ever seen, the silhouette of the giant disk of the South Pole Telescope, where they join a global effort to solve possibly the greatest riddle in the universe: what most of it is made of.

For thousands of years our species has studied the night sky and wondered if anything else is out there. Last year we celebrated the 400th anniversary of Galileo’s answer: Yes. Galileo trained a new instrument, the telescope, on the heavens and saw objects that no other person had ever seen: hundreds of stars, mountains on the Moon, satellites of Jupiter. Since then we have found more than 400 planets around other stars, 100 billion stars in our galaxy, hundreds of billions of galaxies beyond our own, even the faint radiation that is the echo of the Big Bang.

Now scientists think that even this extravagant census of the universe might be as out-of-date as the five-planet cosmos that Galileo inherited from the ancients. Astronomers have compiled evidence that what we’ve always thought of as the actual universe—me, you, this magazine, planets, stars, galaxies, all the matter in space—represents a mere 4 percent of what’s actually out there. The rest they call, for want of a better word, dark: 23 percent is something they call dark matter, and 73 percent is something even more mysterious, which they call dark energy.

“We have a complete inventory of the universe,” Sean Carroll, a California Institute of Technology cosmologist, has said, “and it makes no sense.”

Scientists have some ideas about what dark matter might be—exotic and still hypothetical particles—but they have hardly a clue about dark energy. In 2003, the National Research Council listed “What Is the Nature of Dark Energy?” as one of the most pressing scientific problems of the coming decades. The head of the committee that wrote the report, University of Chicago cosmologist Michael S. Turner, goes further and ranks dark energy as “the most profound mystery in all of science.”

The effort to solve it has mobilized a generation of astronomers in a rethinking of physics and cosmology to rival and perhaps surpass the revolution Galileo inaugurated on an autumn evening in Padua. They are coming to terms with a deep irony: it is sight itself that has blinded us to nearly the entire universe. And the recognition of this blindness, in turn, has inspired us to ask, as if for the first time: What is this cosmos we call home?

Scientists reached a consensus in the 1970s that there was more to the universe than meets the eye. In computer simulations of our galaxy, the Milky Way, theorists found that the center would not hold—based on what we can see of it, our galaxy doesn’t have enough mass to keep everything in place. As it rotates, it should disintegrate, shedding stars and gas in every direction. Either a spiral galaxy such as the Milky Way violates the laws of gravity, or the light emanating from it—from the vast glowing clouds of gas and the myriad stars—is an inaccurate indication of the galaxy’s mass.

But what if some portion of a galaxy’s mass didn’t radiate light? If spiral galaxies contained enough of such mystery mass, then they might well be obeying the laws of gravity. Astronomers dubbed the invisible mass “dark matter.”

“Nobody ever told us that all matter radiated,”Vera Rubin, an astronomer whose observations of galaxy rotations provided evidence for dark matter, has said. “We just assumed that it did.”

The effort to understand dark matter defined much of astronomy for the next two decades. Astronomers may not know what dark matter is, but inferring its presence allowed them to pursue in a new way an eternal question: What is the fate of the universe?

“We have a complete inventory of the universe,” Sean Carroll, a California Institute of Technology cosmologist, has said, “and it makes no sense.”

“Nobody ever told us that all matter radiated,”Vera Rubin, an astronomer whose observations of galaxy rotations provided evidence for dark matter, has said. “We just assumed that it did.”

They already knew that the universe is expanding. In 1929, the astronomer Edwin Hubble had discovered that distant galaxies were moving away from us and that the farther away they got, the faster they seemed to be receding.

This was a radical idea. Instead of the stately, eternally unchanging still life that the universe once appeared to be, it was actually alive in time, like a movie. Rewind the film of the expansion and the universe would eventually reach a state of infinite density and energy—what astronomers call the Big Bang. But what if you hit fast-forward? How would the story end?

The universe is full of matter, and matter attracts other matter through gravity. Astronomers reasoned that the mutual attraction among all that matter must be slowing down the expansion of the universe. But they didn’t know what the ultimate outcome would be. Would the gravitational effect be so forceful that the universe would ultimately stretch a certain distance, stop and reverse itself, like a ball tossed into the air? Or would it be so slight that the universe would escape its grasp and never stop expanding, like a rocket leaving Earth’s atmosphere? Or did we live in an exquisitely balanced universe, in which gravity ensures a Goldilocks rate of expansion neither too fast nor too slow—so the universe would eventually come to a virtual standstill?

Assuming the existence of dark matter and that the law of gravitation is universal, two teams of astrophysicists—one led by Saul Perlmutter, at the Lawrence Berkeley National Laboratory, the other by Brian Schmidt, at Australian National University—set out to determine the future of the universe. Throughout the 1990s the rival teams closely analyzed a number of exploding stars, or supernovas, using those unusually bright, short-lived distant objects to gauge the universe’s growth. They knew how bright the supernovas should appear at different points across the universe if the rate of expansion were uniform. By comparing how much brighter the supernovas actually did appear, astronomers figured they could determine how much the expansion of the universe was slowing down. But to the astronomers’ surprise, when they looked as far as halfway across the universe, six or seven billion light-years away, they found that the supernovas weren’t brighter—and therefore nearer—than expected. They were dimmer—that is, more distant. The two teams both concluded that the expansion of the universe isn’t slowing down. It’s speeding up.

The implication of that discovery was momentous: it meant that the dominant force in the evolution of the universe isn’t gravity. It is...something else. Both teams announced their findings in 1998. Turner gave the “something” a nickname: dark energy. It stuck. Since then, astronomers have pursued the mystery of dark energy to the ends of the Earth—literally.

“The South Pole has the harshest environment on Earth, but also the most benign,” says William Holzapfel, a University of California at Berkeley astrophysicist who was the on-site lead researcher at the South Pole Telescope (SPT) when I visited.

He wasn’t referring to the weather, though in the week between Christmas and New Year’s Day—early summer in the Southern Hemisphere—the Sun shone around the clock, the temperatures were barely in the minus single digits (and one day even broke zero), and the wind was mostly calm. Holzapfel made the walk from the National Science Foundation’s Amundsen-Scott South Pole Station (a snowball’s throw from the traditional site of the pole itself, which is marked with, yes, a pole) to the telescope wearing jeans and running shoes. One afternoon the telescope’s laboratory building got so warm the crew propped open a door.

But from an astronomer’s perspective, not until the Sun goes down and stays down—March through September— does the South Pole get “benign.”

“It’s six months of uninterrupted data,” says Holzapfel. During the 24-hour darkness of the austral autumn and winter, the telescope operates nonstop under impeccable conditions for astronomy. The atmosphere is thin (the pole is more than 9,300 feet above sea level, 9,000 of which are ice). The atmosphere is also stable, due to the absence of the heating and cooling effects of a rising and setting Sun; the pole has some of the calmest winds on Earth, and they almost always blow from the same direction.

Perhaps most important for the telescope, the air is exceptionally dry; technically, Antarctica is a desert. (Chapped hands can take weeks to heal, and perspiration isn’t really a hygiene issue, so the restriction to two showers a week to conserve water isn’t much of a problem. As one pole veteran told me, “The moment you go back through customs at Christchurch [New Zealand], that’s when you’ll need a shower.”) The SPT detects microwaves, a part of the electromagnetic spectrum that is particularly sensitive to water vapor. Humid air can absorb microwaves and prevent them from reaching the telescope, and moisture emits its own radiation, which could be misread as cosmic signals.

To minimize these problems, astronomers who analyze microwaves and submillimeter waves have made the South Pole a second home. Their instruments reside in the Dark Sector, a tight cluster of buildings where light and other sources of electromagnetic radiation are kept to a minimum. (Nearby are the Quiet Sector, for seismology research, and the Clean Air Sector, for climate projects.)

Astronomers like to say that for more pristine observing conditions, they would have to go into outer space—an exponentially more expensive proposition, and one that NASA generally doesn’t like to pursue unless the science can’t easily be done on Earth. (A dark energy satellite has been on and off the drawing board since 1999, and last year went “back to square one,” according to one NASA adviser.) At least on Earth, if something goes wrong with an instrument, you don’t need to commandeer a space shuttle to fix it.

The United States has maintained a year-round presence at the pole since 1956, and by now the National Science Foundation’s U.S. Antarctic Program has gotten life there down to, well, a science. Until 2008, the station was housed in a geodesic dome whose crown is still visible above the snow. The new base station resembles a small cruise ship more than a remote outpost and sleeps more than 150, all in private quarters. Through the portholes that line the two floors, you can contemplate a horizon as hypnotically level as any ocean’s. The new station rests on lifts that, as snow accumulates, allow it to be jacked up two full stories.

The snowfall in this ultra-arid region may be minimal, but that which blows in from the continent’s edges can still make a mess, creating one of the more mundane tasks for the SPT’s winter-over crew. Once a week during the dark months, when the station population shrinks to around 50, the two on-site SPT researchers have to climb into the telescope’s 33-foot-wide microwave dish and sweep it clean. The telescope gathers data and sends it to the desktops of distant researchers. The two “winter-overs” spend their days working on the data, too, analyzing it as if they were back home. But when the telescope hits a glitch and an alarm on their laptops sounds, they have to figure out what the problem is—fast.

“An hour of down time is thousands of dollars of lost observing time,” says Keith Vanderlinde, one of 2008’s two winter-overs. “There are always little things. A fan will break because it’s so dry down there, all the lubrication goes away. And then the computer will overheat and turn itself off, and suddenly we’re down and we have no idea why.” At that point, the environment might not seem so “benign” after all. No flights go to or from the South Pole from March to October (a plane’s engine oil would gelatinize), so if the winter-overs can’t fix whatever is broken, it stays broken—which hasn’t yet happened.

More than most sciences, astronomy depends on the sense of sight; before astronomers can reimagine the universe as a whole, they first have to figure out how to perceive the dark parts. Knowing what dark matter is would help scientists think about how the structure of the universe forms. Knowing what dark energy does would help scientists think about how that structure has evolved over time—and how it will continue to evolve.

Scientists have a couple of candidates for the composition of dark matter—hypothetical particles called neutralinos and axions. For dark energy, however, the challenge is to figure out not what it is but what it’s like. In particular, astronomers want to know if dark energy changes over space and time, or whether it’s constant. One way to study it is to measure so-called baryon acoustic oscillations. When the universe was still in its infancy, a mere 379,000 years old, it cooled sufficiently for baryons (particles made from protons and neutrons) to separate from photons (packets of light). This separation left behind an imprint—called the cosmic microwave background—that can still be detected today. It includes sound waves (“acoustic oscillations”) that coursed through the infant universe. The peaks of those oscillations represent regions that were slightly denser than the rest of the universe. And because matter attracts matter through gravity, those regions grew even denser as the universe aged, coalescing first into galaxies and then into clusters of galaxies. If astronomers compare the original cosmic microwave background oscillations with the distribution of galaxies at different stages of the universe’s history, they can measure the rate of the universe’s expansion.

Another approach to defining dark energy involves a method called gravitational lensing. According to Albert Einstein’s theory of general relativity, a beam of light traveling through space appears to bend because of the gravitational pull of matter. (Actually, it’s space itself that bends, and light just goes along for the ride.) If two clusters of galaxies lie along a single line of sight, the foreground cluster will act as a lens that distorts light coming from the background cluster. This distortion can tell astronomers the mass of the foreground cluster. By sampling millions of galaxies in different parts of the universe, astronomers should be able to estimate the rate at which galaxies have clumped into clusters over time, and that rate in turn will tell them how fast the universe expanded at different points in its history.

The South Pole Telescope uses a third technique, called the Sunyaev-Zel’dovich effect, named for two Soviet physicists, which draws on the cosmic microwave background. If a photon from the latter interacts with hot gas in a cluster, it experiences a slight increase in energy. Detecting this energy allows astronomers to map those clusters and measure the influence of dark energy on their growth throughout the history of the universe. That, at least, is the hope. “A lot of people in the community have developed what I think is a healthy skepticism. They say, ‘That’s great, but show us the money,’” says Holzapfel. “And I think within a year or two, we’ll be in a position to be able to do that.”

The SPT team focuses on galaxy clusters because they are the largest structures in the universe, often consisting of hundreds of galaxies—they are one million billion times the mass of the Sun. As dark energy pushes the universe to expand, galaxy clusters will have a harder time growing. They will become more distant from one another, and the universe will become colder and lonelier.

Galaxy clusters “are sort of like canaries in a coal mine in terms of structure formation,” Holzapfel says. If the density of dark matter or the properties of dark energy were to change, the abundance of clusters “would be the first thing to be altered.” The South Pole Telescope should be able to track galaxy clusters over time. “You can say, ‘At so many billion years ago, how many clusters were there, and how many are there now?’” says Holzapfel. “And then compare them to your predictions.”

Yet all these methods come with a caveat. They assume that we sufficiently understand gravity, which is not only the force opposing dark energy but has been the very foundation of physics for the past four centuries.

Twenty times a second, a laser high in the Sacramento Mountains of New Mexico aims a pulse of light at the Moon, 239,000 miles away. The beam’s target is one of three suitcase-size reflectors that Apollo astronauts planted on the lunar surface four decades ago. Photons from the beam bounce off the mirror and return to New Mexico. Total round-trip travel time: 2.5 seconds, more or less.

That “more or less” makes all the difference. By timing the speed-of-light journey, researchers at the Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) can measure the Earth-Moon distance moment to moment and map the Moon’s orbit with exquisite precision. As in the apocryphal story of Galileo dropping balls from the Leaning Tower of Pisa to test the universality of free fall, APOLLO treats the Earth and Moon like two balls dropping in the gravitational field of the Sun. Mario Livio, an astrophysicist at the Space Telescope Science Institute in Baltimore, calls it an “absolutely incredible experiment.” If the orbit of the Moon exhibits even the slightest deviation from Einstein’s predictions, scientists might have to rethink his equations—and perhaps even the existence of dark matter and dark energy.

“So far, Einstein is holding,” says one of APOLLO’s lead observers, astronomer Russet McMillan, as her five-year project passes the halfway point.

Even if Einstein weren’t holding, researchers would first have to eliminate other possibilities, such as an error in the measure of the mass of the Earth, Moon or Sun, before conceding that general relativity requires a corrective. Even so, astronomers know that they take gravity for granted at their own peril. They have inferred the existence of dark matter due to its gravitational effects on galaxies, and the existence of dark energy due to its anti-gravitational effects on the expansion of the universe. What if the assumption underlying these twin inferences—that we know how gravity works—is wrong? Can a theory of the universe even more outlandish than one positing dark matter and dark energy account for the evidence? To find out, scientists are testing gravity not only across the universe but across the tabletop. Until recently, physicists hadn’t measured gravity at extremely close ranges.

“Astonishing, isn’t it?” says Eric Adelberger, the coordinator of several gravity experiments taking place in a laboratory at the University of Washington, Seattle. “But it wouldn’t be astonishing if you tried to do it”—if you tried to test gravity at distances shorter than a millimeter. Testing gravity isn’t simply a matter of putting two objects close to each other and measuring the attraction between them. All sorts of other things may be exerting a gravitational influence.

“There’s metal here,” Adelberger says, pointing to a nearby instrument. “There’s a hillside over here”—waving toward some point past the concrete wall that encircles the laboratory. “There’s a lake over there.” There’s also the groundwater level in the soil, which changes every time it rains. Then there’s the rotation of the Earth, the position of the Sun, the dark matter at the heart of our galaxy.

Over the past decade the Seattle team has measured the gravitational attraction between two objects at smaller and smaller distances, down to 56 microns (or 1/500 of an inch), just to make sure that Einstein’s equations for gravity hold true at the shortest distances, too. So far, they do.

But even Einstein recognized that his theory of general relativity didn’t entirely explain the universe. He spent the last 30 years of his life trying to reconcile his physics of the very big with the physics of the very small—quantum mechanics. He failed.

Theorists have come up with all sorts of possibilities in an attempt to reconcile general relativity with quantum mechanics: parallel universes, colliding universes, bubble universes, universes with extra dimensions, universes that eternally reproduce, universes that bounce from Big Bang to Big Crunch to Big Bang.

Adam Riess, an astronomer who collaborated with Brian Schmidt on the discovery of dark energy, says he looks every day at an Internet site (xxx.lanl.gov/archive/astro-ph) where scientists post their analyses to see what new ideas are out there. “Most of them are pretty kooky,” he says. “But it’s possible that somebody will come out with a deep theory.”

For all its advances, astronomy turns out to have been laboring under an incorrect, if reasonable, assumption: what you see is what you get. Now astronomers have to adapt to the idea that the universe is not the stuff of us—in the grand scheme of things, our species and our planet and our galaxy and everything we have ever seen are, as theoretical physicist Lawrence Krauss of Arizona State University has said, “a bit of pollution.”

Yet cosmologists tend not to be discouraged. “The really hard problems are great,” says Michael Turner, “because we know they’ll require a crazy new idea.” As Andreas Albrecht, a cosmologist at the University of California at Davis, said at a recent conference on dark energy: “If you put the timeline of the history of science before me and I could choose any time and field, this is where I’d want to be.”

Richard Panek wrote about Einstein for Smithsonian in 2005. His book on dark matter and dark energy will appear in 2011.

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Comments (62)

is dark matter any how relayed to anti matter ??? we know that matter and anti matter repel each other then whhy not antimatter be the reason for the expansion of the universe and why only dark matter???

Posted by on February 9,2013 | 12:35 PM

why should matter be the reason for the expansion of the universe ?????or why should the expansion of the universe suggest the concept of "dark ABC"??????

Posted by on February 9,2013 | 12:29 PM

What if gravity and electromagnetism are expressions or characteristics of Dark energy?

Posted by Hyginus Mathujrin on January 19,2013 | 01:49 PM

So, the energy of dark energy is (in eV)?

Posted by DE on January 6,2013 | 12:02 PM

very insightful, scholarly!

Posted by jude salau on December 24,2012 | 11:45 AM

There are two other profound mysteries...quantum entanglement and the double slit experiment. All three are intangible forces beyond our understanding. All are "immaterial reality," the same definition as the spiritual. Yes, profound.

Posted by joe arrigo on November 16,2012 | 10:00 AM

Encouraging the spirit of discovery and sharing of fundamental knowledge about the Universe and our place in its midst- at http://universalrule.info New Discovery of the Universe- http://t.co/jVFHtSCr Digital Universe- at http://t.co/nsND5lSm found a- Multimedia DEMO “Brief History of the Universe”

Posted by Shahidur Rahman Sikder on October 10,2012 | 07:05 PM

good trial.go on....

Posted by Evan on September 26,2012 | 04:39 AM

Funny that you put some astronomer's names... Funny that you don´t put the name of the astronomer of Big Bang theory... funny...

Posted by Rodrigo Castro on September 19,2012 | 11:13 AM

its that true ?

Posted by rj aganon on September 15,2012 | 07:06 AM

All The Mass Of The Universe Formed At The Pre-Big-Bang Singularity The universe is a two-poles entity, an all-mass and an all-energy poles. The elementary particle of the universe is the graviton. The gravitons are compacted into the universal inert singularity mass only for the smallest fraction of a second, when all the gravitons of the universe are compacted together, with zero distance between all of them. This state is mandated by their small size and by their hence weak force. The big bang is the shattering of the short-lived singularity mass into fragments that later became galactic clusters. This is inflation. The shattering is the start of movement of the shatters i.e. the start of reconversion of mass into energy, which is mass in motion. This reconversion proceeds at a constant rate since the big bang since the resolution of gravitons, their release from their shatters-clusters, proceeds at constant rate due to their weak specific force due to their small size. Dov Henis (comments from 22nd century) http://universe-life.com/

Posted by Dov Henis on September 2,2012 | 10:35 AM

THIS IS MINDBOGGLING!

Posted by Art Ygoña on August 25,2012 | 05:29 PM

THere is essential rules to dimensions. They must interlace there constant properties that define them as an extra dimension to the realm 0f coexisting volumes. A dimension that does not merge into others is not a dimension persay as it is another universe of sorts never to be known by intelligent deduction .Only maybe by chance or accident could this be achieved unless somebody has the time and rescources to take shots in the dark all the time. Even so still yet there maybe no way out if one could get in. space is two dimensional and cannot become only one. I have conclude that there is eleven dimensions and one non-existant void which maybe considered an anti-dimension or 12th realm. I can name all of the dimensions .String theory is not completely right as two dimensional space must allow for quntum flux in particle waves and frequency

Posted by Ken W.Keele on August 15,2012 | 03:34 PM

Why do we need dark energy..?

Posted by Emma on June 19,2012 | 09:31 AM

No force(nothing) in the universe knows that it exist until it connects with light, mattter or gravity. Dark energy is infinite. Before there was any galaxies, universes or anything else there was nothing or infinti.Dark energy is the unexplained or what could have happened in space or time if you were to alter it. This is empty space between dimensions(alternate realities based on human decision). You cannot research or explain the power of nothing. You just get further away at a faster rate similar to a human life, type1A supernova and universal expansion. Everything in the universe eventually becomes nothing(Dark Energy)or just empty space.

Posted by Joseph Mitchell on June 16,2012 | 06:42 AM

It is just dark gravity that leaks across from brane to brane.

Posted by Gilbert Nash on May 17,2012 | 10:12 PM

Secret of a Lifetime How long a neutron lives holds clues to the cosmos http://www.sciencenews.org/view/feature/id/340396/title/Secret_of_a_Lifetime The embarrassingly obvious commonsensical “clue to the cosmos” : From Universe-Energy-Mass-Life Compilation http://universe-life.com/2012/02/03/universe-energy-mass-life-compilation/ A. The Universe From the Big-Bang it is a rationally commonsensical conjecture that the gravitons, the smallest base primal particles of the universe, must be both mass and energy, i.e. inert mass yet in motion even at the briefest fraction of a second of the pre Big Bang singularity. This is rationally commonsensical since otherwise the Big would not have Banged, the superposition of mass and energy would not have been resolved. The universe originates, derives and evolves from this energy-mass dualism which is possible and probable due to the small size of the gravitons. Since gravitation Is the propensity of energy reconversion to mass and energy is mass in motion, gravity is the force exerted between mass formats. All the matter of the universe is a progeny of the gravitons evolutions, of the natural selection of mass, of some of the mass formats attaining temporary augmented energy constraint in their successive generations, with energy drained from other mass formats, to temporarily postpone, survive, the reversion of their own constitutional mass to the pool of cosmic energy fueling the galactic clusters expansion set in motion by the Big Bang. Dov Henis (comments from 22nd century) An Embarrassingly Obvious Theory Of Everything http://universe-life.com/2011/12/10/eotoe-embarrassingly-obvious-theory-of-everything/

Posted by Dov Henis on May 12,2012 | 03:49 PM

Is anyone any wiser about Dark matter and Energy today? I have published a natural solution and even derived MOND but remains ignored perhaps because I cannot get into the professional publications, nevertheless check cosmicdarkmatter

Posted by Tissa Perera on May 7,2012 | 10:58 AM

"Dark matter" aka WIMPS, are anti-matter; what's called anti-matter is actually Transitional matter ( something in between matter and antimatter); this explains Einsteins theories and account for the low density of matter in the observable universe. Wimps are the signature of parallel universes. Here's your nobel prize if you can prove it.

Posted by James Burnett on February 14,2012 | 09:16 PM

Perhaps dark energy/cosmic expansion is simply an affect of a big crunch?

Allow me to elucidate;- When a 'crunch' condenses below its Schwarzchild Radius, I propose a duality is formed, being the Lorentz Transform imaginary (complex number) values associated with 10^12 years.

Posted by David Paul on January 20,2012 | 12:03 AM

According to brane theory two branes touched or bumped into each other at a point and this was the singularity of the big bang.
However if we think of these two branes continuing to contact at an increasingly larger radius moving at a rate greater than the speed of light( relative to our space/time ) would this not explain how inflation occurred?
What if these branes are like soap bubbles and our universe is the contact surface between two of these bubbles. The matter in our universe condensed out of the kinetic energy from this collision.

Posted by Rick Delmonico on January 2,2012 | 10:58 AM

Dark energy may be a property of space itself.
If the nature of the universe is indeed digital then what the speed of light defines for us is the processor speed.

Time, gravity, the stretching out of space and the second law of thermal dynamics are somehow linked in a manner that has yet to be described.

The history of a black hole is written or smeared upon it's rippling surface, called the event horizon. (10-29-10)

The observable universe is just the rippling skin of the real universe.

With each quantum tick of time the the skin or membrane of our universe gets bigger. Einstein tells us that the distinction between the past present and future is a stubbornly persistent illusion. This would suggest that the universe is like a set of Russian dolls nested inside of one another. They all exist but we are stepping from one to the next with every tick of time. From highly energetic and highly ordered to cold dark chaos. As it turns out this is the most likely outcome. 12/2010

If science is to have any chance of grasping the nature of reality, it must first solve the question of how the universe wound itself up through random processes.

Posted by Rick Delmonico on January 2,2012 | 10:21 AM

Did Einstein, as others, reject the idea of Intelligent Design, a Creator God, as the cause of, the Maker of all that is? Some think it intelligent to ask "Then who created God?" Matter and energy all eventually decay and halve their "half life," etc. Something has to have eternal existence back into the past, which is hard for us to grasp. It should help if one remembers this: Something or Someone has to have always existed, BECAUSE if ever there was a time when there was nothing, then there would NEVER be anything, ever!! Something with Creative and Generative Powers had to have always been, ... or we and the whole Universe would never have existed.

Posted by James Averill on December 29,2011 | 02:24 PM

See into- http://digg.com/d31GlVu Encouraging the spirit of discovery and sharing of fundamental knowledge about the Universe and our place in its midst. See visions- Digital Universe http://twitpic.com/4cjmuq see DEMO: found dark energy & big bang!

Posted by Shahidur Rahman Sikder on October 8,2011 | 06:05 PM

Maybe there really isn't any such thing as dark matter. Maybe it's just gravity and that gravity comes from other dimensions. The gravity is just sliping back and forth between the dimensions. The one thing the dimensions share. This would keep the law of coservation in tact. That energy not being created nor destroyed--just transferable. And with energy being consciousness and god and all that jazz it keeps everything as one. Even dimensions. All that exists in any galaxy, universe or dimension is one.

Posted by heyman29323 on September 9,2011 | 02:15 PM

What is Dark Energy? Answer of question- as I see it that of single energy of Power can be called in different name i.e. that means many instances such as: Dark energy, God, Nature, Single dimension, Super power, Black body, Primordial whole, Big black hole, A Black Hole, Borders on the spiritual, Ultimate reality, Huge reserve of the natural force, Primordial whole and eternity present, Absolute zero space-time and physics, and so on. Reality of Creator

Posted by Shahidur Rahman Sikder on August 31,2011 | 06:13 PM

The answer to the dark mystery may be too simple for humans to figure out. The matter that we are made of is 4.507034%. The universe isn't accelerating, but light is slowing down. GM=tc^3, a child could understand it...

Posted by Louise on April 18,2011 | 10:51 AM

For all the GOD believers I ask you this? Who created GOD and for what reason? I have read the Bible The Kiron and even at one time went to Bible study. This is a quote from Einstein one year before his death. " The word GOD is for me nothing more than the expression and product of human weakness, the Bible a collection of honorable but still purely primitive, legends which are nervertheless pretty childish. No interpretation no matter how subtle can (for me) change this." I rest my case!

Posted by Steve on February 15,2011 | 01:24 AM

darkness doesn't exist. it's just the absence of light.

Posted by jhe ar on February 13,2011 | 03:54 AM

you guys are looking at space wrong. think of it like water. if i drop a light into the ocean does it not get dimmer the deeper it falls? and if a fish i can not see swims between the light and myself, will not the light miraculously disappear then reappear? and not knowing how deep the water is because i can not see the bottom, i could perceive it to be endless.

Posted by michael on July 16,2010 | 02:34 AM

It is said that the matter (tangible) in the universe is about 4% of what should have been there. Isn't it possible that the rest of the matter exist in other dimensions? Is that why we can't observe them?

Posted by Anonymous on July 7,2010 | 08:31 AM

DARK ENERGY IS THE MAGNETIC FORCE OF COMBINED PARALLEL SHADOWS OF REVERSE POLARITIES IN RADIATION. ENERGY IN MOLECULAR MOTION EQUALS A PARALLEL NUCLEAR STRUCTURE THAT CONSIST OF (CARBON PRINTS,HOLOGRAMS,PARALLEL DIMENSIONS,INFINITE COSMIC ACCELERATION)DARK ENERGY FEEDS ITSELF AND CLONES ITS SELF IN RETURN MAKES THE DENSITY CONSTANT CAUSING COSMIC ACCELERATION.IN STRUCTURE EXTRA DIMENSIONS ARE THE CAUSE OF EXPANSION .GENERAL RELATIVITY AND QUANTUM MECHANICS IS THE PERSPECTIVE OF MATTER LARGE OR SMALL..IT IS SELF SUFFICIENT AND HAS CONTINUOUS FORCE GRAVITY BEING THE GHOST IN THE MACHINE......ENERGY NEVER DIES

Posted by SIN on May 26,2010 | 11:57 PM

I do not understand why, in the face of such boundless mystery, it so reprehensible within the scientific community to suggest that God has created the universe and put it in motion. I do not think that such a conclusion would take away anything from the validity and worthwhileness of the study of math or science. To accept the reality of God might even enhance our understanding of such disciplines.

Posted by fred stellato on May 9,2010 | 11:24 AM

Mr. Baxter: Did you see my post right above yours? It appears that the "dark energy" is spirit - God said, thousands of years ago, that he would "stretch out the heavens." Apparently He is doing just that. There is no matter involved - just God's will to do that -- perhaps to gain the attention of secular scientists.

Posted by Mary Jefferson on April 29,2010 | 09:20 PM

is it possible that dark energy is invisible because it is of a single homogeneous piece?

for anything to exist, existence must exist first. perhaps dark energy is dense existence itself.

men have long considered the decree to 'know thyself' as valid. perhaps dark energy is another name for this self.

i have seen the self, and it is precisely dense existence per se. perhaps dark energy is another name for it.

thank you, Smithsonian, for publishing such an interesting article, and thank you Dr Turner for pursuing this research.

i hope that Dr Turner will have the opportunity to see this post and consider its implications.

Posted by michael baxter on April 28,2010 | 11:00 AM

In the Smithsonian magazine, the article was accompanied by the statement, "Atronomers are going to the ends of the Earth to study 'dark energy,' a force greater than gravity that will determine the fate of the cosmos." To that statement, I could only say, "Amen!!!"

I once made a list of all the Bible verses that refer to God "stretching out the heavens." Two of my favorites: 1) "He spreads out the northern skies over empty space; He suspends the earth over nothing." Job 26:7 2) "He sits enthroned above the CIRCLE of the earth, and its people are like grasshoppers. He stretches out the heavens like a canopy, and spreads them out like a tent to live in." Isaiah 40:22 (Isaiah lived when the Assyrians were the leading world power - at least in the Near East - which was 200 years +/- before Pythagorus decided the Earth was a sphere.)

The remainder of the list is: Psalm 104:2; Isaiah 41:13, 42:5, 44:24, 45:12; Jeremiah 10:12, 51:15; Zechariah 12:1.
The real "kicker," however (at least in my opinion) is that another great mystery of the universe is that atoms neither collapse nor explode. Colossians 1:15-17 seems to explain that mystery. "He [Jesus of Nazareth] is the image of the invisible God, the firstborn over all creation. For by Him all things were created; things in the heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities, all things were created by Him and for Him. He is before all things and IN HIM ALL THINGS HOLD TOGETHER." (NIV)

Secular scientists seem to try to fit evidence into their pre-conceived notions of the origin and destiny of the universe. Shouldn't the scientific endeavor be a search for the TRUTH, regardless of where it leads?

Posted by Mary Jefferson on April 23,2010 | 02:18 PM

If the universe is expanding, and indeed, that is what is being observed, my query is: into what is the universe expanding? A void? Then again this void, if it exists, is part of the universe. There ought to be a medium beyond the limits of the universe into which it can expand.

Posted by cjsavvy on April 19,2010 | 10:29 PM

I want to buy that book.

Posted by Raul on April 18,2010 | 09:40 PM

Can dark energy be centrifugal force?

Posted by J Stockwell on April 14,2010 | 07:27 PM

Hey RickPietes, since the big bang must have had a beginning point, the matter having expanded out and coelesced from there, then what is beyond the expanded matter? Can you tell me? And if you say that the extent of matter (that includes space) is limitless, then how can there have been a beginning point, with matter having expanded out from it? Crackpot? Look in the mirror.

Posted by James I. Nienhuis on April 14,2010 | 09:39 AM

Dark matter is dark energy that happened the braking effect. The same as happen in the normal matter. The braking effect, at the same time, give the mass and the gravity of the matter (dark or normal). Ramon Marquès

Posted by Ramon Marquès on April 11,2010 | 03:44 PM

My sense for parsimony requires me to postulate that there is at least one great cycle of regeneration in an infinite universe which has existed for an infinite amount of time. This cycle may be called 'the cycle of regeneration of electromagnetic waves'.
This cycle (the precise detail which is beyond my know) involves the very slow absorption of energy from electromagnetic waves (to cause redshift) by dark matter. Dark matter reacts with ordinary matter through gravity. This reaction creates stellar structures which in turn evolve into visible stellar structures such as galaxies. Stellar structures emit large amounts of electromagnetic waves.
An infinite universe is not a closed system for which all the laws of thermodynamics apply.

Posted by andries van den Berg on April 11,2010 | 05:04 AM

I've always wondered how "outer space" could have an edge or limit.Where would space end?

Posted by Dennis Green on April 10,2010 | 02:25 PM

There is the potential of an actual static, not actually taken up yet in physics. A static would have no mass, no wavelength, no fixed location materially, and occupy no set space.

What this static would "do" relative the material world around it in "our" laws of physics is unknown.

Reaearch has been done on this line and indicates a deeper
understanding of the source of energy, and matter in this
"universe".

The obvious avenue for physics is that this universe is a
composite universe. Not just matter and energy in space through time. What else it is made up of may require perception techniques other than through matter and energy.

David Engelhart
Student of Epistimology

Posted by David Engelhart on April 9,2010 | 09:48 PM

What if Time existed in a singularity, held together by the one thing it generated: gravity. When the singularity burst, "The Big Bang", fragments of Time and Gravity inter-acted "quadrillions and quaudrillons" of times, until the only things remaining were the stable hydrogen atoms..with their tiny fragments of gravity.. some small amount of matter, after the matter-anti matter reactions, and clouds of Time and Gravity. We might call these clouds today by the names of Dark Matter and Dark Energy". String theory ain't the answer. It's too ego-centric and anthropomorphic. It ignores what new universes would have to be created if a grain of sand shifted, or a tree leaf fell.

Posted by Ed McClendon on April 8,2010 | 04:46 PM

When first proposed, Einstein's ideas about the curvature of space-time were considered revolutionary, and widely criticized as being fantasy. There is a need for a new set of outlandish ideas to explain what we refer to as dark energy. Currently there aren't even any theories, because there isn't any data to base a theory on. It's highly likely that physics will be changed as much by the new data and ideas as it was by general relativity. Kudos to the scientists who are trying to come up with the ideas, and boo to those readers who attempt some sort of religious or superficial explanation in keeping with their cherished (and severely limited) knowledge.

Posted by Rwk2010 on April 8,2010 | 01:26 PM

My understanding is that, according to the article, the germination of the 'dark matter' theory was to explain why the universe has not expanded to the point of disintegration - dark matter keeps the universe in tact instead of falling apart. And the germination of the 'dark energy' theory was to explain why some sort of 'anti-gravitational force' is causing the universe to expand instead of contract. If the universe is expanding, as described in the latter part of the article, then isn't the universe behaving in a manner scientists expected that it would in the first place? That being the case, why do we need the theories of 'dark matter' and 'dark energy'?

What is it about matter that attracts other matter in the first place? What characteristic does 'mass' have that makes it attract other mass?

At any rate, it is all very interesting and exciting and I hope to live long enough to gain a better understanding.

Posted by Eric on April 8,2010 | 12:49 PM

what could happen if we are ale to exploit dark matter for useful purposes...hmmn

Posted by gina on April 7,2010 | 02:03 AM

@rickpietes

Christians have this silly idea about the Universe being created supernaturally. But by definition "supernatural" means beyond the domain of the known physical laws of the Universe. With this in mind, your statement "no rules of physics" specifically violates that criteria. The Big Bang remains a theory about supernatural origins, though all its proponents seem oblivious to this.

The 2nd Law of thermodyamics is real, so to put it simply, the Universe can't be eternal. It must have had a beginning (if logic is to be preserved). The direct and observable effects of Law 2 also require the universe to be spatially finite (otherwise we would have reached the much anticipated "heat death"). Further we can observe the expansion of the Universe (CMB if you believe it), so Law 1 (conservation of matter-energy) also limits the size of the Universe.

The introduction of dark energy and dark matter is substantially to preserve the Big Bang (long age) model. If Scientists are to resort to the unobservable to support their theories then science (in Cosmoslogy certainly) is dead.

The only reasonable conclusion is fiat creation [sic God and a young Universe/Earth]. Accepting that any naturalistic theory of origins will at some point cross the supernatural threshold, I would suggest that its probably better to accept the reality of a Creator God. Perhaps then funds can be more adequately spent on domestic enterprises.

Reading many of these articles is (for me at least) like watching reality TV; full of cringe-worthy ad-hoc and ill-concieved rationalisations for why so and so is really the greatest talent (read theory) the world has ever witnessed.

Not so, folks, not so.

Posted by Diogmatic on April 7,2010 | 12:08 PM

James I. Nienhuis, what makes you think it was bounded? At the moment prior to the Big Bang (if that is the correct model), no rules of physics, as we currently understand them, apply to that state - certainly no limitations due to space/time, since they don't exist prior to the Big Bang?

armchair crackpot, interesting idea. Sort of like the old paradox of always going half the distance to an objective.

Posted by rickpietes on April 6,2010 | 02:06 PM

Newtonian physics is wrong. A cannonball and a feather in a vacuum will fall close, compared to the six sextrillion ton earth they're falling at, they are virtually the same weight. Light, being incompressibile, shining from every star in the universe is pushing all mass away from it's source, thereby light energy is responsible for the ever expanding universe. Dark energy is clumsy physics. Use light as the functional force and the impingement dynamics will all but explain, and the weaker gravitational forces(distance) exerted. I deduced this logically, and didn't even have to create mysterious terminology, probably won't be popular. Praise god for truth, Rankinstein!

Posted by Hugh Kerby Rankin on April 1,2010 | 07:18 PM

To all who search for the truth:

It is human nature to want to understand. whatever the subject maybe. A theory is generally all anyone has to begin their work. Life as we know it today, would not be possible without all those who came before us following their theory. It seems that each generation feels that with their "advanced equipment" they now have the answers. Some others feel it is waste of money to keep reaching for what, "at this time cannot be proved."

May I respectfully suggest to readers, the steps of learning will never reach an end. Many of us cannot imagine what life will be like in 50-100yrs. For those who will occupy our world, it should be our hope, that all those who strive to learn the truth now, will make their lives safe and in harmony with all nature around them. That is what those who came before us, worked so hard to accomplish.

I was going to write about black matter/energy. Though I am not versed on the subject, it seems that most things in life need negative and positive...attract/repell...gravity anti-gravity. My simple opinion, would see it somewhat as spacers that help to keep order within the system. Though they seem to be causing expansion, perhaps it has always been that way, but our awareness is fairly new.

I wish you all the best and thank you for dedicating your lives to science.

Sincerely,
Ann Stevens

Posted by Ann Stevens on April 1,2010 | 06:10 PM

Has it occurred to anyone at Smithsonian Mag, that what cannot be seen, measured, or verified, might not, in fact, exist?

How do you devote five or six pages of your usually fine journal to a bit of scientism so speculative and un-falsifiable...without even raising the question:

Do these guys really know what they are talking about?

Isn't it worth noting that the Big Bang theory has been falsified in its every iteration - from Father Georges Lemaitre's reconciliation of the Biblical Genesis, with modern astro-physics:

First there was nothing, then BANG, there was everything!

"There was silence on the face of the deep, and the Lord said, let there be light, and there was light."

...to current CMV estimates.

How different are these two creation stories? (Not at all). How similar? (entirely). Is that just coincidence?

Father Georges LeMaitres attempted to correlate Edwin Hubble's observation of a shift into the red of distant objects - even as Hubble himself warned that interpreting reshift as a Doppler effect might be unwise and unwarranted.

Halton Arp then falsified redshift through the observation of contradictory galaxies and celestial bodies: Redshift was more likely a determinate of age, and not distance.

Sir Fred Hoyle had his own problems with the ludicrous and quite Biblical Big Bang 'theory,' so much so that he devised a 'steady state' model to try to better match what is observed.

Kristian Birkeland noted, in the early 20th C., that Earth is bathed and coated with electromagnetic energy. Hans Alfven took the observation further, and revealed that all of outer space courses with electromagnetic energy - a force 10 to the power of 39 times more powerful than gravity.

10 with 39 zeros.

So, who needs "dark matter?"

I take the citation from your otherwise good and serious journal as a last word:

"Michael Turner coined the term "dark energy" in 1998. No one knows what it is." That's because it isn't.

Posted by Liam Scheff on March 31,2010 | 02:28 PM

How do you reconcile the density of material that forms a black hole (in which material seems to be irretrievably lost forever) with the greater density of material that is presumed to have existed at the moment of the Big Bang? As a side note: What is it about the asteroid belt that would keep it from being classified as a "ring around the sun" comparable to the rings around Jupiter, Saturn, etc.?

Posted by GWK on March 27,2010 | 06:37 PM

I'm saying its like a balloon in the reverse,not so much a bang but inflation. The larger the balloon becomes the farther apart objects become. The universe is infinite, but it is only one of many. Like blowing bubbles when they connect sometimes they join. no bang then just inflation.

Posted by acs451 on March 24,2010 | 12:52 AM

Maybe dark energy merely indicates the absence of gravity, rather than opposing it in force?

Posted by Susan Whigham on March 24,2010 | 05:33 PM

In the past.Is it possible that the proportions of dark matter/energy and four dimensional energy were reversed?

Posted by Brian A Jones on March 24,2010 | 12:43 PM

Perhaps the big bang never happened, and the universe has always existed. As you go back in time, approaching the big bang, you can only approach it asymptotically, never quite getting there. Your perception of time merely changes. The first few seconds after the big bang feel like hundreds of billions of years.

The appearance of the big bang would just be an illusion of the universe's tendency to gain entropy over time. You can never reach zero entropy, locally or in the entire universe.

From the perspective of sentient life trillions of years from now, our universe in the present might be perceived as an impossibly hot and cramped universe moments after the big bang.

Posted by armchair crackpot on March 24,2010 | 12:24 PM

The big bang material is the universe, so it must be bounded, according to the model.

Posted by James I. Nienhuis on March 23,2010 | 09:16 PM

Until cosmologists seriously consider the following I fear that the problem of dark energy will remain a problem:
1. The universe is infinitely large.
2. Our Big Bang is probably a finite event in an infinite universe.
3. The Red Shift in starlight is a result of a combination of real movement relative to an observer and another factor that is related to the age of the light in question. The main proportion of Red Shift may be caused by cosmic dust and/or an inherent property of light that causes it to very gradually increase in wavelength. This may be related to the second law of thermodynamics and/or the one way flow of time.

Posted by Andries van den Berg on March 23,2010 | 02:55 PM

The Big Bang Theory, with a beginning point, and matter then expanded out from there, necessitates that matter (the big bang universe) is bounded, having an outer edge, but big bang theorists will tell you the universe is limitless, contradicting the predicate, because if they'd admit the universe must be bounded (according to their own model), the distant stars, because of gravitional time dilation during the rapid expansion of the Big Bang, need be only thousands of years of age, comporting with the biblical model.

Posted by James I. Nienhuis on March 23,2010 | 01:43 PM

i think that the dark energy is what balances the universe and it is what holds every thing in its place.

Posted by tombara on March 23,2010 | 01:28 PM

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Dark Energy: The Biggest Mystery in the Universe

At the South Pole, astronomers try to unravel a force greater than gravity that will determine the fate of the cosmos

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